Systems and apparatus for disinfection of water with ultraviolet light have rapidly developed in view of increased environmental awareness, the accompanying regulation associated with disposal and treatment of waste and potable water and the desire to avoid or reduce reliance on chemical treatment. This growing need has resulted in a similar requirement for producing more efficient and reliable systems for effectively and safely treating waste and potable water over prior art systems.
It is important in achieving this difficult task in ultraviolet treatment systems that all water to be treated, whether passing through an open or closed channel, conduits or the like, is fully treated by exposure to a minimum required quantity of ultraviolet light. Failure of the necessary ultraviolet light dose can result in untreated or improperly treated water and its undesirable consequences. It is accordingly necessary to monitor the ultraviolet light apparatus to insure full coverage of ultraviolet exposure. One means to accomplish this critical task is to directly monitor the intensity of ultraviolet light emanating from one or more ultraviolet light producing lamps utilized in the system. It is important that at least a representative sampling of ultraviolet light intensity be monitored on a continuous basis to ensure that the system provides the necessary dosage of ultraviolet light to the water to be treated.